5 Written questions
5 Matching questions
- does a machine reduce the amount of work that is being done? Explain.
- What two things do we need to know to calculate work?
- And example of a wedge.
- Whats a wheel and axle?
- example of a wheel and axle.
- a turn a door knob (the wheel) the axle moves, to unfasten the door.
- b Doorstop. it holds things together.
- c No, the same amount of work is done, whether you do it yourself, or use a machine.
- d we need to know the size of the force that was put on the object, and how far the object moved.
- e a simple machine that is made of a circular object connected to a rod.
5 Multiple choice questions
- a device that helps make work easier by changing the size or direction of a force.
- a simple machine with a straight, slanted surface.
- Machines can change the size of the input force necessry. Also, they can change the direction of the force, which is especially helpfulo when we are trying to life somthing.
5 True/False questions
What are compound machines? → a machine made of two or more simple machines. example: scissors, can openers
if you are pushing against a wall, are you doing work? explain. → No. work is only done when the object moves. if the object doesnt move, no matter how much force you put on it, it isnt work.
what is mechanical efficiency? → simple machine that is made of a wheel with a groove in it and a rope. it is usually used to life heavy objects.
What is the formula to calculating work? → P=W / T, the unit Watts
^ ---> Doing work? → Yes